Ons toets die wasmasjien Maandag.

Here, ons means we because it is the subject of the sentence.

A useful extra point: ons can also mean us or our in other contexts, but in Ons toets ... it clearly means we.

In Afrikaans, verbs usually do not change form for different subjects in the present tense.

So you get:

• ek toets = I test
• jy toets = you test
• ons toets = we test

That is much simpler than English, where you sometimes get forms like tests.

Die means the.

Afrikaans uses die as the definite article for:

• singular nouns
• plural nouns
• all grammatical genders

So unlike some other languages, you do not have to learn different forms of the for masculine, feminine, or neuter nouns.

Afrikaans often writes compound nouns as one word.

So:

• was = wash / washing
• masjien = machine
• wasmasjien = washing machine

This is very normal in Afrikaans. English often keeps these as two words, but Afrikaans usually joins them.

You know from the noun itself, not from die.

The article die can mean the with both singular and plural nouns, so it does not tell you the number by itself. Here, wasmasjien is singular. The plural would be wasmasjiene.

So:

• die wasmasjien = the washing machine
• die wasmasjiene = the washing machines

Because Afrikaans often places a time expression later in the sentence, especially in a simple main clause like this one.

The basic order here is:

• Ons = subject
• toets = verb
• die wasmasjien = object
• Maandag = time expression

That word order is completely natural in Afrikaans.

Afrikaans often leaves out a preposition before days of the week when giving a time expression.

So English on Monday is often just:

• Maandag

That is why Ons toets die wasmasjien Maandag sounds natural without an extra word before Maandag.

Grammatically, the verb is in the present tense, but in Afrikaans the present tense is often used for a planned future action when the time is clear.

Because the sentence includes Maandag, it will often be understood as something like:

• we test the washing machine on Monday
• we are testing the washing machine Monday

So the exact time sense depends on context, but a future reading is very common here.

Yes. You can say:

Maandag toets ons die wasmasjien.

That is also correct. But when Maandag moves to the first position, the verb must still stay in the second position, so ons comes after toets.

So compare:

• Ons toets die wasmasjien Maandag.
• Maandag toets ons die wasmasjien.

Both are correct, but the second version gives a bit more emphasis to Monday.

Because names of days of the week are capitalized in Afrikaans.

So you write:

• Maandag
• Dinsdag
• Woensdag

not with a small letter.

A rough English-friendly guide is:

vahs-ma-SHEEN

A few notes:

• was sounds roughly like vahs
• sj sounds like English sh
• -ien at the end sounds like the ending of machine

So wasmasjien is pronounced approximately vahs-ma-SHEEN, though the real Afrikaans vowels are not exactly the same as English ones.